Screen deck

ABSTRACT

A screen deck runner assembly ( 20 ) suitable for use in a vibratory screening machine characterized by the assembly including a saddle member ( 5 ), being configured and 420 dimensioned to removably straddle a screen deck runner ( 1 ) and to engage a screen panel ( 3 ).

TECHNICAL FIELD

This invention relates to a screen deck assembly for vibratory screeningmachines.

BACKGROUND ART

Vibratory screening machines are well known in the bulk materialshandling industry. Vibratory screening machines are used particularlyfor the size classification of bulk particulate materials such asmineral bearing ore. Vibratory screening machines usually consist ofscreen decks, supported on a vibratile frame structure, operativelylinked to a motorized vibratory mechanism.

Modular-type screen decks are well known, consisting typically of amatrix of screen panels, generally mounted on a number of steel runners.The steel runners are usually mounted on a steel grid or lattice-typestructure, the grid forming part of the vibratile frame structure. Thevibratile frame structure, together with the motorized vibratorymechanism, is normally supplied by the manufacturer, while specialistscreen deck suppliers add and supply replacement parts such as therunners and the screen panels.

The screen panels and the runners wear as the classified particulatematerial flow across and through the screen panel apertures as well asover the runners. The known designs of the runners are such that,although the runners do not wear as fast as the screen panels, they dohave to be replaced from time to time.

As the runners provide support for the screen panels, they typicallyextend across the whole surface of the screen. The replacement ofrunners therefore usually requires the removal of all the screen panels,the unbolting of the runners from the grid, and the subsequentreplacement of the runners. This procedure is time consuming and labourintensive, causing substantial equipment downtime relative to thereplacement of, for example, a screen panel. When downtime is plannedfor replacement of worn screen panels and/or runners, it typicallyentails production to be stopped or reduced. The wear resistance of thescreen panels as well as the runners are therefore of utmost importanceto reduce wear and consequential downtime of the vibratory screeningmachines during refurbishment, as well as the capital costs of replacingthe worn runners.

It is accordingly an object of the present invention to provide a screendeck runner assembly for vibratory screening machines that overcomes orat least partially alleviates some of the disadvantages mentioned above.

DISCLOSURE OF THE INVENTION

According to the invention there is provided a screen deck runnerassembly suitable for use in a modular-type screen deck for a screeningmachine, the screen deck having a matrix of screen panels, mounted on anumber of steel runners, the runner assembly characterized by a runner,comprising an elongate flat member; and a saddle member, configured anddimensioned to removably straddle the runner in a wear resistant andsecured manner as well as releasable engage a complementary screen panelin an operative arrangement in a screen deck.

The saddle member may have engaging means for engaging the screen panelto the saddle member in a releasable manner therewith, the engagingmeans being integrally formed with the saddle member. Alternatively, theengaging means may comprise a separate fastener member.

The engaging means may comprise a continuous rail-type protrusion, therail being substantially mushroom shaped in cross section and adapted toengage a complementarily shaped screen panel. Alternatively, theengaging means may comprise at least one mushroom-shaped protrusion,adapted to engage a complementary formed screen panel. Furtheralternatively, the engaging means may comprise at least one socketformation, configured and dimensioned to receive a complementary shapedspigot for releasably engaging the screen panel in a spigot and socketconfiguration. The socket formation preferably is provided with anannular sealing ridge provided around the outside of the socket'scircumference.

The engaging means may be made of polymer-type material.

The saddle member may be substantially U-shaped. The saddle member maybe made of high wear resistance polymer type material such aspolyurethane, polyethylene, polypropylene, plastics, nylon or resin. Thesaddle member further may have internal rigid inserts to increase itsstructural rigidity.

The saddle member may be provided with quick release securing means forsecuring the saddle to the runner. The securing means may comprise aspigot and socket arrangement, the saddle and the runner being providedwith complementary apertures for receiving spigots therethrough. Thespigots preferably are of a polymer-type material.

The saddle member further may be provided with load bearing supportformations for operatively supporting the associated screen panelsubstantially along the side of the panel.

Further according to the invention there is provided a screen deckrunner assembly suitable for use in a vibratory screening machinecomprising a saddle member, substantially U-shaped to enable it tostraddle a screen deck runner, the saddle member being adapted forengaging a screen panel and made of high wear resistance polymericmaterial.

The saddle member may have engaging means for engaging the screen panelto the saddle member in a releasable manner therewith, the engagingmeans being integrally formed with the saddle member. Alternatively, theengaging means may comprise a separate fastener member.

The engaging means may comprise a continuous rail-type protrusion, therail being substantially mushroom shaped in cross section and adapted toengage a complementarily shaped screen panel. Alternatively, theengaging means may comprise at least one mushroom-shaped protrusion,adapted to engage a complementary formed screen panel. Furtheralternatively, the engaging means may comprise at least one socketformation, configured and dimensioned to receive a complementary shapedspigot for releasably engaging the screen panel in a spigot and socketconfiguration. The socket formation preferably is provided with anannular sealing ridge provided around the outside of the socket'scircumference.

The engaging means may be made of polymer-type material.

The saddle member may be substantially U-shaped. The saddle member maybe made of high wear resistance polymer type material such aspolyurethane, polyethylene, polypropylene, plastics, nylon or resin. Thesaddle member further may have internal rigid inserts to increase itsstructural rigidity.

The saddle member may be provided with quick release securing means forsecuring the saddle to the runner. The securing means may comprise aspigot and socket arrangement, the saddle and the runner being providedwith complementary apertures for receiving spigots therethrough. Thespigots preferably are of a polymer-type material.

The saddle member further may be provided with load bearing supportformations for operatively supporting the associated screen panelsubstantially along the side of the panel.

Further according to the invention there is provided a saddle member fora screen deck runner assembly of a modular-type screen deck for ascreening machine, the screen deck having a matrix of screen panels,mounted on a number of steel runners, the saddle member comprising asubstantially U-shaped member, configured and dimensioned to removablystraddle a runner in a wear resistant and secured manner as well as toreleasable engage a complementary screen panel in an operativearrangement in a screen deck.

The saddle member may have engaging means for engaging the screen panelto the saddle member in a releasable manner therewith, the engagingmeans being integrally formed with the saddle member. Alternatively, theengaging means may comprise a separate fastener member.

The engaging means may comprise a continuous rail-type protrusion, therail being substantially mushroom shaped in cross section and adapted toengage a complementarily shaped screen panel. Alternatively, theengaging means may comprise at least one mushroom-shaped protrusion,adapted to engage a complementary formed screen panel. Furtheralternatively, the engaging means may comprise at least one socketformation, configured and dimensioned to receive a complementary shapedspigot for releasably engaging the screen panel in a spigot and socketconfiguration. The socket formation preferably is provided with anannular sealing ridge provided around the outside of the socket'scircumference.

The engaging means may be made of polymer-type material.

The saddle member may be substantially U-shaped. The saddle member maybe made of high wear resistance polymer type material such aspolyurethane, polyethylene, polypropylene, plastics, nylon or resin. Thesaddle member further may have internal rigid inserts to increase itsstructural rigidity.

The saddle member may be provided with quick release securing means forsecuring the saddle to the runner. The securing means may comprise aspigot and socket arrangement, the saddle and the runner being providedwith complementary apertures for receiving spigots therethrough. Thespigots preferably are of a polymer-type material.

The saddle member further may be provided with load bearing supportformations for operatively supporting the associated screen panelsubstantially along the side of the panel.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described by way of anon-limiting example and with reference to the accompanying drawingswherein:

FIG. 1 is a perspective cutaway view of a screen deck according to theprior art.

FIG. 2 is a perspective cutaway view of a vibratory screen deck inaccordance with the invention;

FIG. 3 is an exploded view of a screen deck runner assembly.

FIG. 4 is a plan of a saddle member;

FIG. 5 is an elevation view of a saddle member; and

FIG. 6 is a side view of a saddle member;

FIG. 7 is a perspective view of an alternative embodiment of theinvention showing a continuous rail-type engaging means;

FIG. 8 is a perspective view of an alternative embodiment of theinvention showing a mushroom-type engaging means.

FIG. 9 is a perspective view of an alternative embodiment of a screendeck wear saddle according to the invention.

The same reference numerals are use to denote corresponding parts in theaccompanying drawings.

BEST METHOD OF CARRYING OUT THE INVENTION

A prior art screen deck assembly (10) is shown in FIG. 1. Runners (1)are bolted onto a vibratory machine's grid (not shown) by specialistscreen deck suppliers. Runners (1) currently use a T-piece formation (2)at their top edge. Screen panels (3) are placed edge to edge above therunners (1) and connected to the runners by means of securing inserts(4) and securing pins (8), which are inserted into apertures in therunners (not shown).

FIG. 2 shows a screen deck assembly (20) in accordance with theinvention. Runners (1) are bolted onto a vibratory machine's grid (notshown). These runners do not have T-piece formations (2) as shown inFIG. 1. Wear resistant polyurethane, or other suitable material, saddlemembers (5) are placed straddling the top edge of the runners (1). Thesaddle members (5) are fastened to the runners (1) by means of a spigotand socket configuration such as plastic fastening pins (6), which areinserted through aligning fastening apertures (7) in the saddle member(5) and the runner (1).

Screen panels (3) are placed edge to edge above the saddle members (5),and engage with the saddle member (5) and each other by means ofengaging means in the form of polyurethane engaging inserts (4) andpolyethylene engaging pins (8) (see FIG. 3).

Screen panels may be removed by punching the engaging pins (8) throughthe saddle member (5), pulling out the engaging inserts (4) and liftingthe screen panels (3). If the saddle member (5) is worn, the screenpanels (3) are first removed, the fastening pins (8) are punched throughthe runner (1) and the saddle members (5) lifted off and replaced. Theunderlying runners (1) are protected from undue wear by the saddlemembers (5).

In alternative embodiments the saddle member has an integrally formedengaging means in the form of a continuous rail-type engaging means (12,shown in FIG. 7) or a mushroom-shaped protrusion (14, shown in FIG. 8).These engaging means shown in FIGS. 7 and 8 constrain movement of thescreen panel (3) in two degrees of freedom, while the engaging meansshown in FIG. 2 constrains the screen panel in three degrees of freedom.

The embodiments shown in FIGS. 7, 8 and 9 show the saddle member (5)having support formations (18) intermediate along its length on which anedge of the screen panel (3) may be supported. Further, the embodimentsshown in FIGS. 7 and 8 have outwardly flared formations (16) along thelower edge of the saddle member (3) to deflect screened particles (notshown), which have fallen through the screen panels (3), away from therunner (1).

The saddle member (5) has rigid metal inserts (not shown) to addrigidity to the assembly (20).

Where the engaging means for the screen panels (3) is by means of aspigot and socket formation (as shown in FIGS. 2, 3, 4, 5, 6 and 9), theengaging pins (8) are pushed into engaging sockets (9) on the engaginginserts (4). The engaging socket (9) is surrounded by annular ridges(11) shown in on the top surface of the saddle member (5) which sealagainst the bottom of the screen panels (5), thus preventing screenedmaterial from falling into the engaging socket (9) and causing excesswear between the saddle member (5) and the runner (1).

It will be appreciated that many variations in detail are possiblewithout departing from the scope and spirit of the invention,substantially as defined in the consistory statements hereinabove.

1-16. (canceled)
 17. A saddle member for a screen deck runner assemblyof a modular-type screen deck for a screening machine, the screen deckhaving a matrix of screen panels, mounted on a number of steel runners,the saddle member comprising a substantially U-shaped member, configuredand dimensioned to removably straddle a runner in a wear resistant andsecured manner as well as to releasable engage a complementary screenpanel in an operative arrangement in a screen deck.
 18. A screen deckrunner assembly suitable for use in a modular-screen deck for ascreening machine, the screen deck having a matrix of screen panel,mounted on a number of steel runners, the runner assembly including arunner, comprising an elongate flat member; and a saddle member,configured and dimensioned to removably straddle the runner in a wearresistant and secured manner as well as releasable engage acomplementary screen panel in an operative arrangement in a screen deck.19. A screen deck runner assembly as claimed in claim 18 wherein thesaddle member has engaging means for engaging the screen panel to thesaddle member in a releasable manner therewith, the engaging means beingintegrally formed with the saddle member.
 20. A screen deck runnerassembly as claimed in claim 18 wherein the saddle member has engagingmeans for engaging the screen panel to the saddle member in a releasablemanner therewith, the engaging means includes a separate fastenermember.
 21. A screen deck runner assembly as claimed in claim 19 whereinthe engaging means comprises a continuous rail-type protrusion, the railbeing substantially mushroom shaped in cross section and adapted toengage a complementarily shaped screen panel.
 22. A screen deck runnerassembly as claimed in claim 19 wherein the engaging means comprises atleast one mushroom-shaped protrusion, adapted to engage a complementaryformed screen panel.
 23. A Screen runner assembly as claimed in claim 19wherein the engaging means comprises at least one socket formation,configured and dimensioned to receive a complementary shaped spigot forreleasably engaging the screen panel in a spigot and socketconfiguration.
 24. A screen deck runner assembly as claimed in claim 23wherein the socket formation is provide with an annular sealing ridgeextending around the outside of the socket's circumference.
 25. A screendeck runner assembly as claimed in claim 19 wherein the engaging meansis made of polymer-type material.
 26. A screen deck runner assembly asclaimed in claim 18 wherein the saddle member is be substantiallyU-shaped to removably straddle the runner in a wear resistant andsecured manner as well as releasable engage a complementary screen panelin an operative arrangement in a screen deck.
 27. A screen deck runnerassembly as claimed in claim 18 wherein the saddle member is made ofhigh wear resistance polymer type material such as polyurethane,polyethylene, polypropylene, plastic, nylon or resin.
 28. A screen deckrunner assembly as claimed in claim 18 wherein the saddle member is madeof high wear resistance polymer type material such as polyurethane,polyethylene, polypropylene, plastic, nylon or resin.
 29. A screen deckrunner assembly as claimed in claim 18 wherein the saddle member hasreinforcement inserts to increase its structural rigidity.
 30. A screendeck runner assembly as claimed in claim 18 wherein the saddle memberhas quick release securing means for securing the saddle to the runner.31. A screen deck runner assembly as claimed in claim 30 wherein thesecuring means comprises a spigot and socket arrangement, the saddle andthe runner being provided with complementary apertures for receivingspigots therethrough.
 32. A screen deck runner as claimed in claim 31wherein spigot is of a polymer-type material.
 33. A screen deck runnerassembly as claimed in claim 18 wherein the saddle member further isprovided with load bearing support formations for operative supportingthe associated screen panel substantially along the side of the panel.34. A saddle member for a screen deck runner assembly of a modular-typescreen deck for a screening machine, the screen deck having a matrix ofscreen panel, mounted on a number of steel runners, the saddle membercomprising a substantially U-shaped member, configured and dimensionedto removably straddle a runner in a wear resistant and secured manner aswell as to releasable engage a complementary screen panel in anoperative arrangement in a screen deck.
 35. A Screen deck assemblysuitable for use in a modular-type screen deck of a screening machine,the assembly having a matrix of screen panels supported on a grid ofrunners, the runners comprising elongate members; and saddle membersremovably mounted on the runner, each saddle member being configured anddimensioned to straddle at least an upper end of a runner so as toprovide wear resistant shielding thereto, the saddle members beingarranged to extend substantially the full operational length of therunners.
 36. A screen deck assembly as claimed in claim 35 wherein thescreen panels seat on the saddle members and are supported thereon alongthe sides of the screen panels.
 37. A screen deck assembly as claimed inclaim 35 including engaging means for engaging a screen panel to asaddle member in a releasable manner, the engaging means beingintegrally formed with the saddle member.
 38. A screen deck assembly asclaimed in claim 35 including engaging means for engaging a screen panelto a saddle member in a releasable manner, the engaging means comprisinga separate fastener member.
 39. A screen deck assembly as claimed inclaim 38 wherein the engaging means comprises at least one socketformation, configured and dimensioned to receive a complementarilyshaped spigot for releasably engaging the screen panel in spigot andsocket fashion.
 40. A screen deck assembly as claimed in claim 39wherein the socket formation is provided with an annular sealing ridgeextending around the circumference of the socket.
 41. A screen deckassembly as claimed in claim 35 wherein the saddle member issubstantially U-shaped in cross section.
 42. A screen deck assembly asclaimed in claim 35 including securing means for removably securing asaddle to runner, the securing means comprising a spigot and socketarrangement, the saddle and the runner being provided with complementaryapertures for receiving spigots therethrough.
 43. A screen deck assemblyas claimed in claim 35 wherein the saddle member is further providedwith load bearing support formations for operatively supporting theassociated screen panel substantially along the side of the panel.
 44. Asaddle member for a screen deck assembly of a modular-type screen deckof a screening machine, the assembly having a matrix of screen panelsmounted on a grid of runners, the saddle member being adapted removableto be mounted on an associated runner, the saddle member beingconfigured and dimensioned removably to straddle at least an upper endof the associated runner so as to provide wear resistant shieldingthereto, the saddle member being one of a plurality of saddle membersarranged to extend substantially the full operational lengths of therunners.
 45. A saddle member as claimed in claim 44, wherein the saddlemember is substantially U-shaped in cross section.
 46. A saddle memberas claimed in claim 44 including an engaging formation for releasablyengaging the saddle member with a screen panel, wherein the engagingformation comprises at least one socket formation, configured anddimensioned to receive a complementary shaped spigot for releasablyengaging a screen panel in spigot and socket fashion.
 47. A saddlemember as claimed in claim 46 wherein the socket formation is providedwith an annular sealing ridge extending around the circumference of thesocket.
 48. A saddle member as claimed in claim 18 wherein the saddlemember has securing formations for removably securing the saddle memberto s runner, wherein the securing formation comprises a socket aperturefor alignment with a corresponding aperture in a runner, and into whicha spigot may be received.
 49. A saddle member as claimed in claim 44wherein the saddle member is further provided with load bearing supportformations for operatively supporting an associated screen panel at theside of the panel.
 50. A saddle member as claimed in claim 44 whereinthe saddle member is further provided with deflecting formation towardsthe lower edge of the saddle member for operatively deflecting fallingscreened material away from the sides of the runner it is mounted on.